Conventional travel planning services are often provided by human travel agents or multiple searches on many travel service websites by travelers. Planning itineraries and scheduling activities avoiding conflicts are up to the travelers and/or the travel agents. Most of the time, each activity, accommodation, transportation, should be individually reserved at their respective websites. Once set, the itineraries are mostly inflexible or expensive to make any changes even before the travel. Also, during the travel, local weather, traffic, availabilities of activities and locations, may temporarily change but the travelers are usually unable to react to such changes.